The Texas DPS Crime Laboratory Service analyzes an average of 45 gunshot residue (GSR) kits a month using three
different SEM/EDS systems and involving four different analysts. To maintain the volume of cases, we have developed
a robust, cost-efficient method to ensure that all three systems are performing automated GSR analysis within laboratory
specifications, and yielding consistent results across all three systems.
This analysis commonly includes analysis of GSR kits collected from suspects’ hands, but can also include kits from
screening of suspects’ clothing for GSR. Analysts have developed procedures for cleaning and monitoring areas where
clothing and GSR stubs are processed and analyzed in order to ensure that casework stubs were not contaminated in the